Teratoid hepatoblastoma. The nosologic dilemma of solid embryonic neoplasms of childhood.

The presence of divergent tissue, such as bone or osteoid, is a well recognized occurrence in the hepatoblastoma. However, multiple lines of tissue differentiation in a hepatic tumor that had the overall features of hepatoblastoma have recently been observed. During the brief and eventually fatal clinical course in this case, the tumor initially displayed the features of conventional hepatoblastoma, but evolved into a neoplasm with teratoid features, terminally assuming a hepatoma-like appearance. Immunohistochemistry and ultrastructural studies confirmed the various lines of divergent differentiation in this tumor, which the authors chose to designate as a teratoid hepatoblastoma.